It depends on the context, but I would say it is typically for suppressor use, as mentioned above. I don't have a 45 caliber suppressor, but if I did, a subsonic load would be very quiet.

Using a 22 caliber suppressor, there is a big difference in using subsonic vs supersonic ammo. That was one of the original ideas behind the 300 Whisper, which is what the 300 Blackout was based on. It lets you shoot heavy, high B.C. bullets, at subsonic velocities.

I have been working on a subsonic load for a few weeks and I've almost got it fine tuned.The benefits are:Recoil reduction, it's worth it just for that reason alone.Flash reduction, I hog hunt and if you've ever shot a 450 in the dark you'll understand Sound reduction, that's just a bonus.

kobraken wrote:I have been working on a subsonic load for a few weeks and I've almost got it fine tuned.The benefits are:Recoil reduction, it's worth it just for that reason alone.Flash reduction, I hog hunt and if you've ever shot a 450 in the dark you'll understand Sound reduction, that's just a bonus.

Are you achieving the reduced velocity by using a reduced load of one of the standard powders we use for full-bore loads, or are you using a full charge of a slower powder? The carbine length gas system is pretty forgiving, but I can not see a rifle length system tolerating the reduced pressure without enlarging the gas port hole. Even then, it would be a messy load as far as blow-back into the gas impingement system. If you are using reduced loads of standard powders we use, be careful of reducing the charge too much. What weight bullets are you using for your subs? Without serious resizing effort of the heavier .458 bullets, about the heaviest jacketed bullet you're going to find in .451-.452 is 325gr. Of course, at subsonic velocities, heavy cast boolits would be a good application with the right gas check, AKA tall checks.

Hoot

In Theory, there is no difference between theory and practice. In Practice, there is.

I've used two adjustable gas blocks and in both cases, I went for two features. They had to be steel so that they expanded and contracted at something approaching the same rate as the barrel when their temperature changed. Preferable Stainless Steel either in the white or blackened with some treatment. They had to be cheap. In the case of the first one I got, that' meant blocks that were not possessing some of the more useful properties like at a minimum, a set screw to lock the gas adjustment screw. My first one did not have that and that meant needing to utilize some thread locker to keep it where it was set. Not a good idea if you are going to be messing with different loads. There are not so cheap designs now that have either a detente that provides a tactile click every certain number of degrees of rotation. That can be a plus when documenting how far you turned it open, past closed, for a given load you intend to use again. Another feature that comes with a price, but is useful is one that has a lever or knob you can turn without a tool which you will at some point forget to take with you to the range. Lastly is a block that has its surfaces treated with a finish that either discourages carbon buildup or at the minimum cleans easier than just being parkerized. The second block I bought had a set screw and a melonited finish and it does clean up after prolonged use a lot easier. If you are using a handguard that is so long that it covers the gas block, you will be relegated to buying a low profile gas block. Your choice of value added features goes down if you are constrained to low profile, but do get one where the gas adjustment is accessible from the end facing the muzzle so you don't have to remove the handguard to adjust it.

That's all that comes to mind. One last point. Good looks doesn't always mean good cookin'. Don't fall for eye candy, cool logo types where the manufacturer put more of the cost into presentation than performance.

Hoot

In Theory, there is no difference between theory and practice. In Practice, there is.

I'll be first to say I don't know squat on subloads, but would think you'd need to open the gas port up to get more pressure back to the carrier, an adjustable gas block will only meter the pressure your ports putting out now. Maybe move the port back to like a pistol length would help.

I'm guessing the 458 Socom has been explored to death for subs, might get some starting point ideas with a quick google search.

Al in Mi wrote:I'll be first to say I don't know squat on subloads, but would think you'd need to open the gas port up to get more pressure back to the carrier, an adjustable gas block will only meter the pressure your ports putting out now. Maybe move the port back to like a pistol length would help.

I'm guessing the 458 Socom has been explored to death for subs, might get some starting point ideas with a quick google search.

I just assumed that he asked about an adjustable block because we was going to open the port to accommodate subsonics and you, me, everyone knows how Ass U Me breaks down, so point Al.

We can finally own and use suppressors in "save us from ourselves" Minnesota, but the price tag and more importantly, my lack of patience has kept me from exploring them. The "Walter Middy" in me would love to experiment with making one, but being on the government's radar doesn't thrill me. I'd rather put some money into a sound suppressing bullet trap for down in the shop. My wife was a nervous wreck a few years back when I was fire-forming 300 OSSM brass. The rolled up carpet got rid of the high frequency components but there was a low frequency rumble every time I let one go that propagated through the house and I'm in a completely concrete enclosed shop attached to the basement.

Hoot

In Theory, there is no difference between theory and practice. In Practice, there is.

An adjustable gas block is my next step,as changing the position on the barrel is not an option.Hoot--- can you suggest a good,quality block such as what you describing? I've got a friend who can install it for me,just need to get the right one.